RENTON — For Zach Johnson, the regional scouting combine at the Seattle Seahawks’ facility on Saturday offered his first real opportunity to show what he could do in front of NFL scouts.

The Eastern Washington University product had not been cleared by doctors from labrum shoulder surgery in January, so Johnson did not participate at his school’s pro day two weeks ago.

“I just wanted to get some numbers since I didn’t do it on pro day for scouts to see,” Johnson said. “And I tested as a safety. I played linebacker my whole career. And so I’ve been trying to do that, and I’m a little lighter. I wanted to open some eyes with that.”

At 6-foot and 212 pounds, the Tumwater High graduate will have to make the transition from outside linebacker to safety as a professional. Johnson put up decent numbers in his testing, running the 40-yard dash in 4.64 seconds and posting a vertical jump of 39.5 inches.

Johnson’s twin brother Matt, who also played for EWU, was a fourth-round draft pick last year by Dallas.

“It definitely helped,” Johnson said about his brother getting drafted by the Cowboys. “He was hoping to play, but had injuries last year. But it just lets me know what needs to be done, and kind of the mental aspect of it.”

Johnson was one of 275 players looking to impress scouts during testing and positional work. As expected, the Seahawks had a large contingent of scouts and coaches on hand, including offensive line/assistant head coach Tom Cable, senior personnel executive Scot McCloughan and director of pro personnel Tag Ribary.

The NFL prospects are hoping to join about 200 players in the super regional combine beginning April 7 at Cowboys Stadium in Arlington, Texas, where representatives from all 32 NFL teams will attend.

Several Seattle players stopped by to take in the action, including safeties Earl Thomas and Kam Chancellor, defensive end Bruce Irvin and tight end Sean McGrath.

A Chicago native, McGrath was discovered at a regional scouting combine last year, and was eventually invited to the super combine in Detroit. Safety Jeremy Rodenburg, McGrath’s former teammate at Henderson State in Arkadelphia, Ark., participated in the regional combine in Seattle.

“Any time you can get yourself in front of scouts and get that type of exposure, especially coming from a small-time school – any opportunity counts,” McGrath said. “If you’re out there, they’re going to find you. And this is kind of another opportunity for a guy coming from my situation, from a small-school background – or perhaps a guy who’s been out a little bit that still wants to chase his dream – this is a great opportunity.”

Receiver Kyle Bolton from Baker University, an NAIA school in Baldwin City, Kan., posted the fastest 40-yard time of 4.29 seconds, although at 5-foot-9 and 185 pounds, he has some size issues.

Safety Jay-T Rysaac, who played at NAIA Georgetown (Ky.) College, posted the fastest time among defensive players in the morning group, running 40 yards in 4.44 seconds. Even more impressive: Rysaac is 33 years old.

But perhaps the most impressive athlete was University of Idaho defensive end Benson Mayowa, who, at 6-3 and 252 pounds, ran the 40 in 4.65 seconds and had a 38-inch vertical jump.

Former pro basketball player and Lincoln High graduate Maurice Shaw looked like he belonged on the field, running the 40 in 4.81 seconds, and moving well in agility drills at 6-10, 265 pounds.

Puyallup High and Washington State University product Isaiah Barsh, who plays for the Seattle-Tacoma Cobras of the Professional Developmental Football League, relished the chance to show his talent in front of scouts. Barsh, a linebacker, said he’s planning to compete in Buffalo’s rookie minicamp in May.